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Cotton and Climate Change The Untold Story Kai Hughes Executive Director International Cotton Advisory Committee International Cotton Advisory Committee
Cotton and Climate Change The Untold Story
Kai HughesExecutive DirectorInternational Cotton Advisory Committee
International Cotton Advisory Committee
What Causes Climate Change?Deforestation for Land UseEnergy: Electricity & Petroleum ProductsChemicals: Fertilizers, Pesticides, Synthetic fibres, Dyes etc.,
What Changes Most?Greenhouse gases (CO2, CH4, N2O etc.)Temperature anomaliesRainfall patterns Drought intensitiesFrequency of extreme events
www.icac.org
1. What Causes Climate Change?Deforestation for Land UseEnergy: Electricity & Petroleum ProductsChemicals: Fertilizers, Pesticides, Synthetic fibres, Dyes etc.,
2. What Changes Most?Green house gases (CO2, CH4, N2O etc.)Temperature anomaliesRainfall patterns Drought intensitiesFrequency of extreme events
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Atmospheric CO2 Concentration
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www.icac.org
Global Warming Projections
Fischer et al., Geophysical Research Letters, 2014
Rainfall Patterns Are Strongly Influenced by Global WarmingErratic Monsoon, Frequent Floods & Drought
www.icac.org
Cotton Is a Victim of Climate Change
Cotton Helps to Mitigate Climate Change
International Cotton Advisory Committee
CombatingClimate Change
Soil Organic matter
Temperature resilient varieties
COMBATING CLIMATE CHANGE
• Breeding for Temperature Tolerant Cultivars
• Promote Regenerative Agricultural Practices
www.icac.org
What Does Climate Change Mean to Cotton?
• Increase in atmospheric CO2 even up to doubled levels of 840ppm benefits cotton1
• But even a small increase in mean temperatures (1oC) depresses yields and quality1
• Global warning significantly influences rainfall patterns2. Therefore, rainfed cotton farms such as those in Africa will be worst affected
1Raja Reddy, 20202Fischer et al., Geophysical Research Letters, 2014www.icac.org
Impact of CO2 and Elevated Temperatures
on Cotton
www.icac.org
Cotton, Wheat, Rice, Sunflower
Maize, Sorghum, Sugarcane
Cotton is a C3 plant It can use high levels of CO2 (900 ppm) for photosynthesis
www.icac.org Raja Reddy, 2020
Cotton grows well even at 820 ppm of CO2
www.icac.org Raja Reddy, 2020
www.icac.org
Scientific StudiesHigher CO2 Levels Benefit Cotton but
High Temperatures can Lower cotton Yields
Raja Reddy, 2020
28-30 27-35 27-32 24-27 Germination Seedling growth Square growth Boll size and retention
Optimum Temperature oC
Min Temp (night) >27oC causes sterile pollen, small bolls & boll shedding
>38oC impedes growth rate
>30oC reducesgermination%
Day / Night Temperatures oC20/12 25/17 30/22 35/27 40/32
Seedling Growth at Different Temperatures
3-Weeks Old
www.icac.org Raja Reddy, 2020
Boll Weight Boll Retention
Higher TemperaturesDecrease Boll Weight &
Cause Poor Boll Retention
www.icac.org Recalculated from Raja Reddy, 2020
>27oC >32oC
Optimum 24-27oC
Temperature oC
Higher Temperatures Affect Fibre Quality
Fibre Qualities
Length Strength
Micronaire Uniformity
www.icac.org Raja Reddy, 2020
Rainfed Cotton Could Be Most Affected
>98% African Cotton Is Rainfed
International Cotton Advisory Committee
https://public.wmo.int/en/media/press-release/earth-day-highlights-climate-action
Global Warming Patterns
www.icac.org
Predicted Climate Change, GDP Interactions Across Africa
www.icac.org
45-year Data in Cameroon
Gérardeaux, E., et.al.,2013. Agronomy for sustainable development, 33(3), pp.485-495.www.icac.org
Global Warming will Decrease Seed Cotton Yield in Burkina Faso
Diarra, A et. al., 2017. African Journal of Agricultural Research, 12(7), pp.494-501.www.icac.org
The Role of Cotton in Mitigating
Climate Change Effects
International Cotton Advisory Committee
• Cotton farming can help in mitigating the effects of climate change1
• Cotton sequesters 23% more CO2eq of GHGs than it emits2
• With regenerative agricultural practices the crop can sequester even more CO2eq of GHGs2
• Cotton fabrics biodegrade in soil within 4-12 weeks, whereas synthetic fabrics do not3
Cotton Can Minimise Climate Change Effects!
1 Cotton Incorporated, LCA UPDATE OF COTTON FIBER AND FABRIC LIFE CYCLE INVENTORY, 20172Fischer et al., Geophysical Research Letters, 2014
3Source: Cotton Works
• Plants absorb CO2 and sequester carbon in their biomass • Cotton plants do more…they use CO2 and H2O to create cellulose• Cotton fibres are 96-98% pure cellulose (C6H10O5)n• Cotton sequesters 0.5 Kg additional CO2 per Kg fibre produced• Cotton is a C3 plant and has great capacity to use CO2• Organic cotton has very low carbon footprint
Cotton Is Special in Reducing
Atmospheric CO2
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Greenhouse Gas Emissions in the Cotton Value Chain
Cotton Production 5-10%Manufacture 20-30%Consumer Use 30-60%
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Irrigation, Fertilisers, Pesticides and Energy in Production, Processing and Consumer Use Are the Main Contributors
CO2 eq Emissions in Life Cycle of a T-Shirt
Grace (2009). The impacts of carbon trading on the cotton industry.www.icac.org
0 1 2 3 4 5 6 7 8 9
Flax
Cotton
Silk
Viscose
Polypropylene
Polyester
Acrylic
Nylon
Cotton Emits Fewer CO2 eq of GHGs per Kg Fibre in Production
Moazzem et al., Journal of Fiber Bioengineering and Informatics 11:1 (2018) www.icac.org
Recycled Polyester T-Shirt
Cotton Jersey, Bleached, Softened
Recycled Polyester T-Shirt
Cotton Jersey, Bleached, Softened
Week-0
Week-0
Week-12
Week-12
Cotton Biodegrades in Soil in 12 Weeks, Polyester Does Not
Source: Cotton Works www.icac.org
Cotton wipes biodegrade quickly in a composting container 100% cotton: 92 – 95% in four weeksBlend: Cotton biodegraded; Polypropylene did not
Textile Waste Management 1960-2015
https://www.sewdynamic.com/pages/polyester-industrywww.icac.org
In 12 weeks the landfills will be left with only the poorly-degradable synthetic textiles
What Can We Do to Make Cotton Resilient to Climate Change?
www.icac.org
• Breed temperature tolerant cultivars
• Reduce dependence on fertilisers & chemical pesticides
• Rejuvenate soil health through regenerative agriculture practices
• Promote cotton as a carbon sequestering crop and an eco friendly biodegradable fibre
Thank You
International Cotton Advisory Committee
